My Inquiry
My Account
Analog Devices Inc./Maxim Integrated MAX6866UK33D3S+T
- Part No.:
- MAX6866UK33D3S+T
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Category:
- Supervisors
- Package:
- SC-74A, SOT-753
- Datasheet:
-
MAX6866UK33D3S+T.pdf
- Description:
- IC SUPERVISOR 1 CHANNEL SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:4,702
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
The MAX6866UK33D3S+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in a 5-pin SOT23 package, featuring ultra-low 170nA typical supply current, a factory-trimmed 3.3V reset threshold (±2.5%), 300ms minimum reset timeout, and integrated watchdog timer with 3.3s typical timeout. It monitors VCC, responds to manual reset (MR), and asserts an active-low open-drain RESET output - ideal for battery-powered glucose monitors and portable medical devices requiring reliable brownout protection.
For engineers reviewing the MAX6866UK33D3S+T datasheet, MAX6866UK33D3S+T pinout, MAX6866UK33D3S+T application, or MAX6866UK33D3S+T equivalent, this page delivers verified technical context, exact pin functions, real-world use cases, and validated alternative options - all grounded in Maxim's official specifications for the precise part number.
Technical Context
The MAX6866UK33D3S+T integrates voltage monitoring, manual reset input (MR), and watchdog timer functionality in a single BiCMOS IC. Its reset assertion is triggered by VCC falling below 3.3V, MR pull-down, or WDI inactivity exceeding 3.3s (typ), with guaranteed reset validity down to VCC = 1.1V.
It uses a precision bandgap reference for threshold stability (±2.5% over temperature), features 200ns MR glitch rejection, and provides 150ns minimum WDI pulse width detection. The open-drain RESET output requires an external pullup and supports logic-level interfacing across 0–5.5V domains.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reset Threshold | 3.3V ±2.5% - factory-trimmed for accurate brownout detection at nominal 3.3V rail |
| Supply Current | 170nA typ at +25°C - enables multi-year operation on coin-cell batteries |
| Reset Timeout | 300ms min (D3 option) - ensures µP completes power-up initialization before release |
| Watchdog Timeout | 3.3s typ (S suffix) - balances fault coverage and software execution margin |
| VCC Validity Range | 1.1V to 5.5V - guarantees functional reset assertion even during deep brownout |
| WDI Pulse Width | 150ns min - detects fast firmware toggles without missing watchdog clears |
| MR Glitch Rejection | 200ns - suppresses noise-induced false resets in noisy portable environments |
Pinout & Package
Package: 5-pin SOT23-5, lead-free, -40°C to +85°C operating range.
| Pin | Circuit Role | Design Meaning |
|---|---|---|
| 1 | RESET | Active-low open-drain reset output; requires external pullup; sinks current only when asserted |
| 2 | GND | Ground reference for all internal circuits and reset timing; must connect to system ground plane |
| 3 | MR | Active-low manual reset input; internally pulled up to VCC via 10kΩ; accepts CMOS logic levels |
| 4 | WDI | Watchdog input; rising/falling edges clear internal timer; latched high/low >3.3s triggers reset |
| 5 | VCC | Supply voltage input and monitored rail; bypass with 0.1µF capacitor to GND for noise immunity |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-low ICC | 170nA typical supply current enables >10-year battery life in coin-cell–powered devices |
| Immune to VCC transients | Rejects ≤40µs transients at 100mV overdrive - prevents spurious resets in noisy power rails |
| Guaranteed reset at low VCC | Valid RESET assertion down to VCC = 1.1V - ensures reliability during deep brownout recovery |
| No external components | Self-contained supervision: no capacitors, resistors, or trimming required for basic operation |
| Open-drain RESET flexibility | Supports level-shifting to µP I/O voltages up to 5.5V - simplifies mixed-voltage system design |
Applications
| Glucose Monitors | Patient Monitoring Devices |
|---|---|
|
Use Scenario: Portable handheld glucose meters powered by CR2032 coin cells with intermittent usage over multi-year shelf life. IC Role / Device Role / Timing Role: Supervises 3.3V analog front-end and MCU supply; asserts RESET during battery voltage sag or firmware hang. Use Value: Prevents erroneous glucose readings caused by undervoltage MCU operation or unresponsive firmware - critical for clinical accuracy and safety compliance. |
Use Scenario: Wearable ECG patches with Bluetooth LE connectivity, operating on rechargeable Li-ion cells with dynamic load profiles. IC Role / Device Role / Timing Role: Monitors main 3.3V system rail and triggers watchdog reset if BLE stack freezes or sensor acquisition halts. Use Value: Ensures continuous physiological data capture by recovering from firmware lockups without user intervention - meeting IEC 60601-1 reliability requirements. |
| Smart Pagers | Industrial Handheld Terminals |
|
Use Scenario: Low-power two-way pagers receiving infrequent alerts, spending >99% of time in deep sleep with RTC running. IC Role / Device Role / Timing Role: Provides power-on reset and monitors VCC during wake-up bursts; MR allows hardware-initiated reboot after failed OTA update. Use Value: Eliminates need for external reset IC or RC network - reduces BOM count and PCB area while maintaining fail-safe boot integrity. |
Use Scenario: Ruggedized barcode scanners used in warehouse logistics, exposed to ESD and power fluctuations from USB-C charging. IC Role / Device Role / Timing Role: Guards against brownout-induced flash corruption during write cycles; WDI tied to scanner's main loop heartbeat signal. Use Value: Prevents field failures due to corrupted firmware or invalid memory states - directly supporting ISO 13849-1 functional safety goals. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar microprocessor supervisory applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX6864UK33D3S+T | Same 3.3V threshold, D3 timeout, S-watchdog, but push-pull active-low RESET output | Requires no external pullup; not suitable where level-shifting or wired-OR reset bus is needed | Select when driving a single µP with dedicated reset line and minimal external components |
| TPS3836K33DBVR | 3.3V threshold, 200ms timeout, no watchdog; 1.6µA ICC (vs. 170nA); SOT23-5 pin-compatible | Lacks WDI functionality; higher current draw limits battery lifetime in ultra-low-power designs | Choose only if watchdog is unnecessary and cost is prioritized over nanopower operation |
Compared with MAX6866UK33D3S+T, MAX6864UK33D3S+T offers simpler drive capability but forfeits open-drain flexibility, while TPS3836K33DBVR trades off 10× higher supply current and no watchdog - making MAX6866UK33D3S+T uniquely suited for long-life, safety-critical, watchdog-dependent portable medical systems.
Availability
MAX6866UK33D3S+T is available at Aetrix Electronics and suitable for glucose monitors, patient monitoring devices, smart pagers, and industrial handheld terminals requiring stable component supply across extended production lifecycles.
Supply support for MAX6866UK33D3S+T includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Maxim Integrated (now part of Analog Devices) designs precision analog, mixed-signal, and power management ICs for demanding industrial, medical, and communications applications.
The MAX6854–MAX6869 family was engineered specifically for nanopower microprocessor supervision in battery-constrained portable medical and consumer electronics - emphasizing ultra-low ICC, guaranteed low-VCC operation, and integrated watchdog reliability.
FAQ
What is the exact reset threshold voltage of the MAX6866UK33D3S+T?
The MAX6866UK33D3S+T has a factory-trimmed reset threshold of 3.3V with ±2.5% tolerance over -40°C to +85°C. This value is confirmed in Table 2 (Threshold Suffix Guide) and Electrical Characteristics, where VTH = 3.3V (min 3.218V, typ 3.300V, max 3.383V). The '33' in the part number explicitly denotes the 3.3V threshold variant.
Does the MAX6866UK33D3S+T include a watchdog timer, and what is its timeout?
Yes, the MAX6866UK33D3S+T includes a watchdog timer with a typical timeout of 3.3s, indicated by the 'S' suffix in the part number. Per Table 3 (Watchdog Timeout), the S option specifies min 1.5s, typ 3.3s, max 7.75s. The timer resets on any WDI edge and expires only if WDI remains static beyond this period.
What type of RESET output does the MAX6866UK33D3S+T provide?
The MAX6866UK33D3S+T provides an active-low open-drain RESET output (Pin 1), as confirmed in the MAX6864/MAX6865/MAX6866 Pin Description section and Selector Guide. This requires an external pullup resistor and enables wired-OR reset buses or level-shifting to higher-voltage logic domains.
What is the minimum reset timeout period for the MAX6866UK33D3S+T?
The MAX6866UK33D3S+T has a minimum reset timeout period of 300ms, specified by the 'D3' suffix. Table 4 (Reset Timeout Periods) confirms D3 = min 150ms, typ 225ms, max 300ms. This ensures sufficient hold time for µP initialization sequences after power stabilization.
Is the MAX6866UK33D3S+T compatible with 1.8V or 2.5V supply rails?
Yes, the MAX6866UK33D3S+T operates across VCC = 1.1V to 5.5V and monitors a fixed 3.3V threshold regardless of actual VCC level. It functions correctly with 1.8V or 2.5V µPs when used as a dedicated 3.3V rail supervisor - e.g., supervising a 3.3V LDO that powers lower-voltage logic.
MAX6866UK33D3S+T Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Series:
- -
- Package/Case:
- SC-74A, SOT-753
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Type:
- Simple Reset/Power-On Reset
- Number of Voltages Monitored:
- 1
- Voltage - Threshold:
- 3.3V
- Output:
- Push-Pull, Totem Pole
- Reset:
- Active Low
- Reset Timeout:
- 150ms Minimum
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-5
MAX6866UK33D3S+T FAQ
1.How can I place an order for MAX6866UK33D3S+T through Aetrix?
Please submit a Request for Quotation (RFQ) for MAX6866UK33D3S+T on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for MAX6866UK33D3S+T reliable?
The price and inventory of MAX6866UK33D3S+T are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MAX6866UK33D3S+T is usually 5 days.
3.What payment methods are accepted for MAX6866UK33D3S+T?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MAX6866UK33D3S+T transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MAX6866UK33D3S+T?
MAX6866UK33D3S+T orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MAX6866UK33D3S+T order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for MAX6866UK33D3S+T?
For technical support, including MAX6866UK33D3S+T datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MAX6866UK33D3S+T requirements.
6.How does Aetrix verify that MAX6866UK33D3S+T is sourced from the original manufacturer or authorized distributors?
All MAX6866UK33D3S+T products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that MAX6866UK33D3S+T meets industry standards.
7.What is the process for return or replacement of MAX6866UK33D3S+T?
All MAX6866UK33D3S+T units undergo pre-shipment inspection (PSI). If there is an issue with MAX6866UK33D3S+T, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The MAX6866UK33D3S+T part is unused and in its original packaging.
Return procedure for MAX6866UK33D3S+T:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MAX6866UK33D3S+T Tags
-
MIC826SYMT-TR
Microchip Technology
-
APX803S-31SA-7
Diodes Incorporated
-
APX803L20-29SA-7
Diodes Incorporated
-
TPS3828-33DBVR
Texas Instruments
-
V6340RSP3B+
EM Microelectronic
-
EM6325CXSP5B-2.9+
EM Microelectronic
-
MCP120T-300I/TT
Microchip Technology
-
MCP130T-315I/TT
Microchip Technology
-
MCP120T-475I/TT
Microchip Technology
-
MCP111T-300E/TT
Microchip Technology
-
MCP120T-315I/TT
Microchip Technology
-
MCP809T-315I/TT
Microchip Technology
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
